This is a competitive renewal of NIH T32DK-07519, requesting funding for years 26-30 for 4 pre- and 5 post- doctoral positions, and also 3 short-term summer slot positions for minority students. The aim is to continue training the next generation of scientists in the clinically-relevant medical area of the regulation of hematopoietic cell production. Pre- and post-doctoral trainees will be trained 3-4 and 2-3 years, respectively.We assembled an outstanding group of 27 productive/interactive investigators from 7 departments of the medical school (Microbiology/Immunology, Biochemistry/Molecular Biology, Pharmacology/Toxicology, Medical/ Molecular Genetics, Medicine, Pediatrics, and General Surgery) who have trained pre- and/or post- doctoral students with multidisciplinary approaches using different cell types, and who have collectively co- published over 1000 papers with their students. Training emphasis is on hematopoietic stem (HSCs) and other blood cells, but includes studies with other cell types to enhance collaboration/training experiences. The PD studies HSCs and hematopoiesis, published >650 papers, is on numerous editorial boards/NIH/other review/advisory committees, is President of ASH, and has trained 66 pre/post docs. The Co-PD is well- recognized in the hematopoiesis area, has published >140 papers, trained >20 students/fellows, and served on numerous grant review committees. Our preceptors are funded, have extensive collaborations, co-publish with each other, have our labs within 5-10 minute walking distance, and are dedicated to training students in the area of this program. Training entails one-on-one interactions, formal committee meetings, lab meetings, special seminar series and journal club, didactic courses, ethical training and scientific meeting presentations. An Internal and External Advisory Committee monitors student/mentor and PD/Co-PD progress. Many of our past students are employed in academia. This training will enhance the future of hematopoietic cell regulation for basic understanding and translation for treatment of disease. PUBLIC HEALTH RELEVANCE: Elucidating the basic biology of blood cells is crucial for understanding malignant and non-malignant hematopoietic disease initiation and progression, and means to successfully treat these disorders. This training will provide the next generation of scientists in this exciting, but still not fully-realized translational and clinical, discipline of blood cell production for the health benefit of our citizens.